银掺杂聚吡咯包覆石墨复合材料的制备

Preparation of Graphite Decorated with Silver-Doped Polypyrrole Composites

摘要: 以硝酸银为氧化剂，引发吡咯单体在石墨载体上发生化学原位聚合反应，同时硝酸银被还原成银粒子掺杂于聚吡咯中，制备得到以石墨为核、银掺杂聚吡咯为壳的银掺杂聚吡咯包覆石墨复合材料。通过SEM、XRD和FTIR分析分别对复合材料的微观形貌、物相组成和结构进行了表征，通过TGA分析研究了复合材料的热稳定性，采用四探针测试了复合材料的电导率并探讨了反应温度和pH对电导率的影响。研究表明：复合材料中聚吡咯与石墨之间存在着某些相互作用，有助于提高复合材料的热稳定性；当反应时间和反应物物质的量固定时，反应温度为40˚C、pH为1.9时，复合材料的电导率可达到18.037 S∙cm⁻¹。

Abstract: Graphite decorated with silver-doped polypyrrole (Ag/PPy/C) composites were prepared by chemical in-situ polymerization of pyrrole monomer on graphite support using silver nitrate as the oxidant. Silver nitrate was reduced to silver particles and doped into polypyrrole. So the composite has a core-shell structure with graphite as core and silver-doped polypyrrole as shell. The morphology, phase composition and structure of the composite were characterized by SEM, XRD and FTIR. The thermal stability of the composite was analyzed by TGA. The conductivity of the composite was tested by four probes and the effect of temperature and pH on conductivity were discussed. Results show that there are some interactions between polypyrrole and graphite in the composite, which helps to improve the thermal stability of the composite. When the reaction time and the amount of reactant materials are fixed, the reaction temperature is 40˚C and the pH is 1.9, the conductivity of the composite can reach 18.037 S∙cm⁻¹.